Anguiano was last seen at the laundromat inside her apartment complex in the 900 block of Illinois Avenue in Los Banos, California at 10:30 or 10:45 p.m. on August 21, 1999. A neighbor saw Anguiano speaking to Adolfo Romo Martinez prior to the time she vanished. Martinez is her former live-in boyfriend and the father of her two toddler-age children. The neighbor saw them talking for almost an hour; Anguiano had her back to wall and Martinez was standing directly in front of her with both hands against the wall, questioning her aggressively. Anguiano left her clothes inside the dryer and her children asleep in her apartment, which she shared with a cousin. She has never been seen again.

Martinez had physically abused Anguiano throughout their relationship; following their breakup, he continued to threaten her and occasionally was violent towards her. She had gotten a court order for child support from him; he had to pay her $440 a month and he resented it. He questioned the paternity of their children and didn't want to support them, although testing proved he was their father. After Anguiano's disappearance, authorities determined Martinez had lied about where he was at the time she vanished.

Authorities charged Martinez with Anguiano's abduction and presumed murder shortly after her disappearance. Martinez was convicted of second-degree murder and false imprisonment in July 2000, though prosecutors had not found Anguiano's body or any physical evidence. He was sentenced to eighteen years to life in prison and his appeal was denied in 2002. Anguiano has never been located.